CMSC858F: Algorithmic Lower Bounds: Fun with Hardness Proofs
نویسندگان
چکیده
1. For any instance I1 of π1, I2 = f(I1) is an instance of π2 such that OPTπ2(I2) ≤ OPTπ1(I1). 2. For any feasible solution S2 of I2, S1 = g(I1, S2) (g maps S2 into an instance of I1) we have Costπ1(I1, S1) ≤ Costπ2(I2, S2). Note that OPTπ2(I2) ≤ OPTπ1(I1) ≤ Costπ1(I1, S1) ≤ Costπ2(I2, S2). Therefore, if there is an approximation factor ∆ for π2 then there is an approximation factor ∆ for π1 as well.
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